Thank you for contacting Telerik support.
Here is a sample code how to achieve this by using the TimeSlotCreated event:
sender, TimeSlotCreatedEventArgs e)
RadScheduler scheduler = (RadScheduler)sender;
(e.TimeSlot.Start.DayOfWeek == DayOfWeek.Sunday || e.TimeSlot.Start.DayOfWeek == DayOfWeek.Saturday)
You can also review this on-line demo
where similar behavior have been implemented.
Hope this will be helpful. If you have further questions I will be glad to assist you again.
the Telerik team
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